I don't mind little ones tbh, like most people, cast, location and sort of a mini plot, that gives you some idea of what might happen, but nothing that's going to give everything away!
Like when the BBC released those pictures on the Who site the day before the Impossible Astronaut aired, that really annoyed me, as the Doctor Who news page is one of my home pages tabs, and I saw it, and for me that was definitely a spoiler too far. I personally don't get why people want to know MASSIVE spoilers and ruin everything for everyone else! I don't mind waiting for things, as like they say, good things come to those who wait... wait and you'll enjoy it more than knowing what is going to happen. That's what I say...
Basic plot, cast/characters and setting that's my limit